Display screen or portion thereof with an animated graphical user interface



FIG. 1 is a front view of a display screen or portion thereof with an animated graphical user interface showing a first image in the sequence our new design;

FIG. 2 is a second image thereof; and,

FIG. 3 is a third image thereof.

In the drawings, the two outermost broken lines illustrate the display screen. The other broken lines illustrate portions of the graphical user interface. No subject matter depicted in the broken lines form part of the claimed design.

The appearance of the animated images sequentially transitions between the images shown in FIGS. 1-3. The process or period in which one image transitions to another forms no part of the claimed design. 

CLAIM We claim the ornamental design for a display screen or portion thereof with an animated graphical user interface, substantially as shown and described. 